Capillary malformation, or 'port-wine stain'is a common cutaneous vascular anomaly that appears as a red macular stain that darkens over years.

Referred to as birthmarks, capillary malformations consist of dark red, nonelevated, sharply circumscribed patches which blanch on pressure with a glass, leaving a residual brown hyperpigmentation.

Capillary malformation is a frequent birthmark in the newborn infant, especially located in the central forehead; it fades spontaneously over a few months or years, as a rule.

Predisposition

 familial capillary malformation (MIM.608354)

• Locus 5q13.3: germline mutations in the RASA1 gene (#14639529#)

 combined vascular malformative syndromes

• Sturge-Weber syndrome (MIM.185300)
• Klippel-Trenaunay syndrome (MIM.149000)
• Parkes Weber syndrome (MIM.608355).

Associations

 arteriovenous malformation (arteriovenous fistula)